The first line of the calculation is the same procedure as multiplying with a single digit number. In the second line we are multiplying by \(20\) (two tens). As we are multiplying by tens the unit's ...

19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...

Four Wappingers elementary students are multiplying up to 384-digit numbers in school. These students, who are in the district's math enrichment program, are getting creative with math theory to solve ...